YOU only use a few grains of powder. the cost is very small compared to the rest of it. the fire forming in the dies is acomplished by a special tool that screws onto the die (not done in the press) with a spring loaded pin like a firing pin you insert the case with powder(only10 grains of bullseye )and then pack with corn meal and caped with wood glue into a trim die screw on the fire form tool and snap the pin and wala a formed case. there is a pic of how this tol is hand made on page 50 of the handloaders manual of cartridge conversions. This book it a MUST!!!!!!!!!!!!!! if you are going to start wildcating your own stuff. 10 grains of powder and a primer are only going to cost a few cents and you can do this in the shop no trip to the range required. and npo wear on your barrel. I dont see how else you are going to make what you want with out spending a few hundred dollars on special forming dies. the other way to fire form it is to ream a old barrel or rod with your reamer and fire form in it.